The long term objectives of the present studies are to improve the human outcomes from primary cardiac arrest and from serious injury leading to arrest. The specific aims of this application are: 1) To provide evidence of the University of Alabama at Birmingham's (UAB) ability to participate in multicenter resuscitative clinical trials that will evaluate strategies to improve outcomes from primary cardiac arrest and from traumatic injuries leading to arrest. 2) To document the local network of assembled resources capable of implementing in- and out-of-hospital resuscitation protocols. 3) To demonstrate UAB's ability to develop resuscitation protocols for implementation at the national level. 4) To determine whether responding emergency medical services personnel should perform three minutes of chest compressions prior to defibrillating a person who has been in ventricular fibrillation or pulse-less ventricular tachycardia for five minutes or greater or whether immediate defibrillation results in improved survival to hospital discharge. 5) To determine if the administration of dehydroepiandrosterone (DHEA) to seriously, but non-fatally injured patients during resuscitative efforts administered during the first 120 minutes in the receiving emergency department will result in improved clinical outcomes. 6) To expand UAB's on-going commitment to the training of clinical scientists in the field of resuscitation and emergency medicine through the development of a Clinical Research Skills Development Core and subsequent trainee participation in the Consortium.